1. Field of the Invention
The invention concerns a mobile apparatus having at least one wheel which is rotatable about a wheel axle, a main body which is mounted swingingly on the wheel axle and the centre of gravity of which is beneath the wheel axle, a compensating weight which compensates for oscillating movements of the main body about the wheel axle and which is movable in a defined manner by means of a regulator from the normal rest position in which the overall centre of gravity of the main body and the compensating weight is disposed perpendicularly with respect to the wheel axle, and a drive device provided on the main body for driving the at least one wheel of the mobile apparatus.
2. Description of the Prior Art
Such a mobile apparatus is known from DE 31 03 961 C2. In that known mobile apparatus, the compensating weight for compensating for oscillating movements of the main body about the wheel axle is formed for example by a battery pack. Defined displacement of the battery pack is effected by means of a simple pendulum mechanism as the regulator, which is mounted on the center line of the mobile apparatus and which regulates an electric motor and a screwthreaded rod in such a way that the battery packxe2x80x94like the slide or tool carriage of a turning lathexe2x80x94moves to and fro, as is described in column 3, lines 20ff. This publication does not set forth more detailed information as to how that pendulum mechanism operates.
The object of the invention is to provide a mobile apparatus of the kind set forth in the opening part of this specification, in which regulation of the compensating weight which compensates for oscillating movements of the main body of the apparatus about the wheel axle is automatically and independently effected simultaneously with the drive of the at least one wheel of the mobile apparatus, while rotational moments resulting in tilting or rocking of the main body are immediately compensated.
In accordance with the invention, in a mobile apparatus of the kind set forth in the opening part of this specification, that object is attained in that the wheel axle of the at least one wheel has a differential which is operatively connected to the drive device and which is arranged between the at least one wheel and an associated pinion which is operatively connected to the associated regulator and to the associated compensating weight or to the compensating weight formed by the respective regulator.
In a mobile apparatus in accordance with the invention of such a configuration therefore there is advantageously no need for electronic or other additional devices in order to promptly compensate for an undesired rotational moment which would result in tipping or rocking of the main body about the wheel axle of the mobile apparatus. In the case of the apparatus according to the invention the regulator acts against such an undesired rotational moment or an undesired rotational pulse just as long as is required to maintain the dynamic equilibrium.
The at least one compensating weight of the mobile apparatus according to the invention can be provided in per se known manner with a servo hydraulic or a servo pneumatic system which, during the duration of the corresponding rotational pulse, ensures exact displacement of the corresponding compensating weight into the required direction. The construction with said servo hydraulic system or servo pneumatic system affords the further advantage that frictional resistances in the corresponding regulating section can be eliminated.
In the mobile apparatus according to the invention, the respective differential can be operatively connected to the drive device by means of a drive shaft, a drive wheel fixed on the drive shaft, and an output wheel which is fixed to the differential housing and which meshes with the drive wheel. Said drive wheel can be for example a bevel drive wheel and the output wheel can be a ring gear, as are known from conventional differentials. The output wheel is connected to a brake disk.
It is desirable in the mobile apparatus according to the invention if the regulator has a main portion fixed to the main body and a displacement portion which is disposed linearly movably on the main portion and which has a toothed rack meshing with the pinion, wherein a spring device is provided between the main portion and the displacement portion. The spring device preferably has two identical spring elements of which the one spring element, upon displacement of the displacement portion, is loaded in tension and the other spring element is loaded in compression, and vice-versa. The two spring elements do not have to be fixedly stressed between the displacement portion and the main portion. In that case, only one spring element is correspondingly loaded upon each displacement of the displacement portion.
The arrangement affords a rotational pulse-controlled regulating system with pulse take-off by way of the at least one differential which outputs the respective rotational pulse by way of the wheel axle and the associated pinion and by way of the two spring elements between the main body which is fixed with respect to the vehicle and the displacement portion provided thereon, and converts it directly into a corresponding displacement of the associated compensating weight. In that way the mobile apparatus or its main body which is mounted swingingly on the wheel axle is prevented from performing an oscillating movement about the wheel axle.
The above-mentioned spring elements of the spring device can be formed for example by coil springs or by other correspondingly acting elements such as gas springs or the like.
A compact configuration for the mobile apparatus according to the invention is afforded if the displacement portion of the regulator is provided with the compensating weight and thus directly forms the compensating weight. In this case, the direction of movement of the regulator for the equilibrium condition is to be produced by a suitable transmission effect.
The mobile apparatus according to the invention may be a single-wheel single-axle vehicle, a two-wheel single-axle vehicle or a multi-axle vehicle. In the case of a multi-axle vehicle the wheels of one side of the vehicle can be viewed as an ideal wheel. That ideal wheel is determined by the circle which touches the end wheels of the respective side of the wheel, that is to say embraces same in contacting relationship. The axis of that ideal wheel, in such a vehicle, is the above-mentioned wheel axle, in regard to the overall center of gravity.
In the case of the single-axle two-wheel vehicle, a respective wheel can be provided at each of the two mutually remote end portions of the wheel axle, in which case associated with each of the two wheels is a differential and a regulator as well as a common compensating weight, while it is possible to provide on the wheel axle a central differential which is operatively connected to the compensating weight. When the mobile apparatus is of such a design configuration, a central drive wheel can be fixed on the differential housing of the central differential and meshes with a central output wheel, and the compensating weight which is movable along a linear guide device can have a toothed rack which meshes with the central output wheel.
In the above-described design configuration of the mobile apparatus therefore the compensating weight is displaced with a regulated linear movement in order to definedly avoid, that is to say compensate for, oscillating movements of the main body of the mobile apparatus about the wheel axle. It is however also possible for the pinion which is fixed to the wheel axle to be connected to a pendulum weight which forms the compensating weight. That pendulum weight can be for example a body which is in the shape of a segment of a disk.
The invention affords a rotational pulse-controlled regulation effect with pulse take-off by way of a differential, wherein the pendulum weight converts the respective rotational pulse into a rotational or pivotal movement which pivots and correspondingly raises the pendulum weight, whereby the main body of the apparatus is relieved of load in the reaction to the corresponding rotational pulse, this signifying compensation for the oscillating movement of the main body about the wheel axle.
The mobile apparatus according to the invention affords the advantage that the vehicle, that is to say its main body which is mounted swingingly on the wheel axle, is prevented from performing a rocking or seesaw movement. That applies both in regard to mobile apparatuses which roll on a base or those which are suspended on a rail or on a cable. A further advantage is that the mobile apparatus according to the invention does not require starting regulators or electric motors as a drive device. That gives rise to the further advantage that the risk of non-functioning as a result of failure of electrical or electronic parts of the mobile apparatus is eliminated as an equilibrium is maintained between the rotational moment generated by the drive device and the compensating rotational moment produced by the compensating weight, by motor power. In a similar manner, mass inertia upon braking maintains the condition of equilibrium to the required extent.
As the regulating mechanism converts the rotational moment triggered by acceleration (or braking)xe2x80x94insofar as it is not absorbed by the at least one wheel of the mobile apparatusxe2x80x94into a regulated displacement of the compensating weightxe2x80x94and more specifically just as much as the at least one wheel does not absorb rotational moment forcexe2x80x94there is the further advantage that the mobile apparatus according to the invention is suitable for normal on-road traffic. In that respect even insensitive control of the respective vehicle does not give rise to any difficulties. The principle in accordance with the invention represents an advantageous development even in the case of per se known multi-axle vehicles, from safety aspects.
In the case of vehicles according to the invention which are suspended on cables or rails, use of the principle according to the invention affords the advantage that it is possible to start and decelerate more rapidly and briskly than hitherto, because at any time corresponding oscillating movements of the main body of the apparatus about the wheel axle are reliably compensated in a simple manner. For such vehicles which are suspended from cables or rails, that results in a greater maximum speed which is reasonable in regard to the safety demands of the passengers of such a vehicle.
Further details, features and advantages will be apparent from the following description of an embodiment of the mobile apparatus according to the invention, as is diagrammatically shown in the drawing: